A projector type lamp using an LED as a light source is provided as a lamp of an automobile, for example, a headlamp. In this type of lamp, a light source and an optical system for irradiating light emitted from the light source with a required light distribution are included as a unit. JP-A-2013-45601 (PTL 1) discloses a vehicle lamp including a lamp unit in which an LED module is configured by mounting an LED on a power feeding board made of ceramic with high thermal conductivity and the LED module is attached to a heat sink together with an optical system.
Such a light source unit needs a configuration for electrically connecting to an external power supply to make the LED emit light. Further, such a light source unit is required to be disposed in a specific positional relationship with respect to an optical member such as a reflector or a projection lens for irradiating light emitted from the LED toward the front of the lamp.
In JP-A-2013-45601, the LED module is positioned and attached to the heat sink by using an attachment. In this manner, the LED module is positioned and electrically connected to the external power supply by a wiring member provided in the attachment.
In JP-A-2013-45601, the power feeding board constituting the LED module is made of ceramic which is a thermally-conductive insulating member. The reason is that an insulating member with high thermal conductivity is used so as to form a wiring member for feeding power to the LED on the power feeding board and to improve the heat dissipation effect of heat generated when the LED emits light. In general, since the power feeding board made of ceramic is expensive, the LED module or the lamp unit including such LED module is also expensive.
Further, in JP-A-2013-45601, the attachment for positioning and mounting the LED module on the heat sink is provided so as to improve the light distribution characteristic of the lamp unit. Therefore, the number of parts of the lamp unit is increased. Further, since the attachment forms the wiring member for feeding power to the LED, the structure is complicated and expensive, and the lamp unit becomes more expensive.
An object of the disclosure is to provide a lamp unit capable of reducing the number of parts and achieving low cost without deteriorating the heat dissipation effect and the light distribution characteristic, and a method of manufacturing the lamp unit.